1. Field of the Invention
The present invention relates to devices and mechanical means for rotating an axle, shaft or spindle. It relates more particularly to knobs and crank handles for actuating axles and to devices for mounting and fixing them on these axles.
2. Description of the Prior Art
It is known that, for this purpose, axles generally of circular cross-section, have at their end for receiving the knob or the crank handle, one or two flats, or a polygonal cross-section cooperating with corresponding one or two flats or polygonal section provided on the knob or the crank handle. Furthermore, to render these elements fast to one another, recourse is had to a fixing and tightening screw, cooperating or not, as the case may be, with a tapped hole provided on the axle, which screw must unavoidably be turned by means of a screwdriver before and after the assembly or mounting of the elements. Moreover, in the case of the existence of a hole tapped at the shaft end, this mounting and this fixing are effected by manipulating the parts so that the screw is presented exactly facing this hole and so that the straightness of this positioning is ensured and preserved in the course of tightening.